code: def update(self, metric: float) -> bool:
      if self.should_update(metric):
          self.best = metric
          return True
      return False
  
imports: from dataclasses import field
  from typing import Dict, Any, Optional
  from typing_extensions import Literal
  import numpy
  import mxnet
  from mxnet import gluon
  import mxnet.gluon.nn
  from gluonts.core.component import validated
  from gluonts.pydantic import dataclass
  from .callback import Callback
label_desc: Use image node_id 2 for calling the Objective obj's underlying member method code with example usage: obj.update(metric) and returns: False, True